why shoulda can be handy

test.rb

# without shoulda 
test "invalid name gives error message" do 
  @z.name = nil 
  assert_presence(@z, :name)
end


# with shoulda

class ZombieTest < ActiveSupport::TestCase 
  should validate_presence_of(:name)
  should validate_presence_of(:graveyard) 
  should ensure_length_of(:name).is_at_most(15) 
  should have_many(:tweets)
end

# more
should validate_uniqueness_of(:name) 
should ensure_length_of(:password).is_at_least(5).is_at_most(20) 
should validate_numericality_of(:age) 
should_not allow_value("blah").for(:email) 
should allow_value("a@b.com").for(:email) 
should ensure_inclusion_of(:age).in_range(1..100) 
should_not allow_mass_assignment_of(:password) 
should belong_to(:zombie) should validate_acceptance_of(:terms_of_service)

pretty cool.. declarative rather than imperative